Learn how the proposed FDA rule to regulate laboratory-developed tests (LDTs) as medical devices will potentially limit patient access to essential medical care.

Informational Resources From ARUP and Industry Partners, Webinar Recording, and Key Dates

new icon  Read ARUP’s response to a request for information from Senator Bill Cassidy, MD (R-LA), on the regulatory framework for diagnostics under the FDA and the Clinical Laboratory Improvement Amendments (CLIA) here.

new icon  Read ARUP’s public comment for the House Committee on Energy and Commerce Subcommittee on Health here.

Webinar Recording Now Available

Watch ARUP’s Jonathan Genzen, MD, PhD, chief medical officer and senior director of governmental affairs, have a conversation with ARUP’s compliance officer, Jonathan Carr, JD, about the FDA’s proposed rule to regulate LDTs as medical devices. This 60-minute webinar was recorded Wednesday, November 29, at 11 a.m. In the webinar, they addressed patient safety, test availability, and the impact on innovation. They also responded to questions from attendees that were submitted before and during the Q&A.

Webinar Presenters

Jonathan GenzenJonathan Carr


Due to the limited time and the many questions received before and during the webinar that were not addressed, Dr. Genzen has provided written answers on this page. All webinar recipients will also receive an email addressing those questions.


Key Dates Related to FDA Proposed Rule


September 29, 2023: FDA announced proposed rule: Medical Devices; Laboratory Developed Tests.


October 2, 2023: ARUP joined industry partners in opposing the proposed rules.


October 21, 2023: In a letter, 89 laboratories, including ARUP, and industry groups requested that the FDA extend the 60-day comment period.


October 31, 2023: FDA denied the extension.


November 28, 2023 ARUP’s Formal Public Comment to FDA


December 4, 2023: Deadline for public comment


ARUP and Industry Partner Resources

American Clinical Laboratory Association (ACLA) and American Hospital Association (AHA) Release Formal Opposition to FDA’s Proposed Rule to Regulate LDTs

ACLA called the proposal "misguided" and called for continued conversations regarding legislation to further regulate LDTs. Read more.

AHA said LDTs are critical for patient access to timely diagnostic information for many conditions for which no FDA-approved test exists. Read more.

Yale Experts: The FDA’s Proposed Rule on Lab-Developed Tests Could Have Unintended Consequences

“We’re actually seen more problems with the FDA-cleared commercial tests than we have with our laboratory developed tests,” said Marie-Louise Landry, MD, professor of laboratory medicine and of medicine (infectious diseases). Read more.

Association for Diagnostics and Laboratory Medicine (ADLM): FDA Goes All in to Regulate Laboratory Developed Tests

If the FDA finalizes its proposal to regulate LDTs, it is likely that the agency will face lawsuits, which could delay implementation of the rule and could set up a Supreme Court fight. Read more.

Association for Diagnostics & Laboratory Medicine Laboratories Podcast

Octavia Peck Palmer, PhD, director of the Division of Clinical Chemistry at the University of Pittsburgh, talks with Dennis Dietzen, PhD, medical director of Laboratory Services at St. Louis Children’s Hospital, about why the proposed FDA rule could hinder patient access to essential LDTs. Access podcast here.

ARUP Article on Panel Discussion at Utah Life Sciences Summit

ARUP Expert: FDA Plans to Further Regulate Laboratory-Developed Tests May Stifle Innovation, Harm Patients

ARUP LabMind Podcast

Meghan Delaney, DO, MPH, division chief of Pathology and Laboratory Medicine at Children’s National Hospital in Washington, D.C., joins Dr. Genzen to explain that LDTs she develops are often FDA-approved tests that must be modified to ensure they are effective for use in children. Listen here.

Letter to FDA Commissioner Robert M. Califf, MD, From 89 U.S. Laboratories and Industry Groups

Read the letter.

American Clinical Laboratory Association Press Release

ACLA Opposes Unilateral FDA Action to Regulate Laboratory Developed Tests Under Medical Device Authority

ARUP Article on Results of Study Examining Use and Impact of LDTs on Patient Care

New ARUP Study Characterizes the Use and Importance of Laboratory-Developed Tests as Congress Considers the VALID Act